Resumen
Climate warming and environmental problems caused by the excessive consumption of fossil energy and massive CO2 emissions have seriously damaged the human living environment. This paper develops a new green, efficient, and environmentally friendly CO2 capture and conversion method, which is a crucial way to alleviate the greenhouse effect. In this study, alkali metal carbonates (and the corresponding hydroxides) are fused and blended to construct a liquid molten salt electrolyte system with excellent performance, which is applied to synthesize carbon materials or carbon-based fuel gas. By regulating the electrolyte composition and electrolysis parameters, carbon-based fuels with different micro-morphologies and compositions can be prepared in a controllable manner. In pure Li2CO3 electrolyte, carbon nanotubes (CNTs) with a high value are synthesized at 750 °C with, initially, 10 mA/cm2 and, finally, with 100 mA/cm2. Carbon spheres are obtained in Li-Ca-Ba at 750 °C with 200 mA/cm2, while honeycomb carbon is generated in the electrolyte of Li-Na-K at 450 °C with 450 mA/cm2. Syngas (33.6%) or CH4-rich fuel gas (40.1%) can also be obtained by adding LiOH into the electrolyte under 500 °C at 2.0 V and 3.2 V, respectively. This paper provides a new way of utilizing CO2 resources and a new sustainable green development.